class Solution {
    public boolean checkIfPangram(String sentence) {

        boolean[] has=new boolean[26];
        for(int i=0;i<sentence.length();i++){
            int c=sentence.charAt(i)-'a';
            has[c]=true;
        }
        for(int c=0;c<26;c++){

            if(!has[c]){
                return false;
            }
        }
        return true;
    }
}